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Muscle Fiber Contractions: A Case Study

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Muscle Fiber Contractions: A Case Study
Muscle Fiber contractions for our purposes begins with the arrival of action potential (action potential- is an electrical current) at the end of the axon terminal (axon terminal- the swollen distal end of the motor neuron axon). When the action potential reaches the axon terminal the action potential causes the voltage- gated calcium ion channels to open allowing calcium to flow in from extracellular fluid. The presence of calcium in the axon terminal causes synaptic vesicles (synaptic vesicles- small membranous sacs that contain the neurotransmitter acetylcholine also known as ACH) to fuse with the axon terminals axonal membrane. Once fused with the axonal membrane the synaptic vesicles release acetylcholine into the synaptic cleft (synaptic
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